Flotation apparatus



A. W. FAHRENWALD.

FLOTATION APPARATUS.

APPLICATION FILED MAY 1|, 1920.

3,417,895. Patented May 3G, 19;?2.`

2 SHEETSSHEET 1.

' A. W. FAHRENWALD.

FLOTATION APPARATUS. 112151101111011 111511 111AY11,1920.

Afm/19895 Patented May 30, 1922.

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

ARTHUR W. FAHRENWALD, OF MOSCOW, IDAHO.

FLOTATION APPARATUS.

To ,ZZ whom t may concern Be it known that I, ARTHUR W. FexHItnN` wALD, a citizen of the United States, and a resident of Moscow, in the county of Latah and State of Idaho, have invented certain new and useful Improvements in Flotation Apparatus, of which the following is a specification.

My invention relates generally to a flotation apparatus for recovering valuable min eral from their ores, and particularly to that class of flotation apparatus in which the recovering process is effected by circulation and aeration.

The purpose of my invention is the provision of a flotation apparatus of that character which maintains the ore pulp in continuous circulation at the same time subjecting it to aeration, the latter process being controllable at will so that its intensity can be :increased or decreased in accordance with the particular character of the pulp being treated.

I will describe one form of flotation apparatus embodying my invention and will then point out the novel features thereof in claims.

In the accompanying drawings:

Figure 1 is a View showing in side elevation one form of flotation apparatus ernbodying my invention, a portion .of the tank being broken away to reveal the arrangement of the impeller within the tank.

Figure 2 is a view showing in front elevation the apparatus shown in Figure 1.

Figure 3 is a vertical sectional view of the impeller shown in Figure l.

Figures 4, 5, and 6 are transverse sectional views taken on the lines 4 4, 5-5 and 6 6,

respectively, of Figure 3.

Referring specifically to the drawings and particularly to Figures 1 and 2, F designates a suitable form of frame to which is secured, in the manner shown in Figure 1, a. tank designated at T. The tank T is of the contour shown in Figure 1, open at the top'and its forward and upper end formed with a discharge lip 17. The lower end of the tank terminates in the discharge nipple or spout 18 which is normally closed by a plug 19. Also at each side of the tank there is suitably mounted a glass panel 15. The forward wall 16 of the tank is inclined `as shown and within the tank is positioned an upstanding plate 20 which is designed to prevent retrograde movement of the ore pulp Specification of Letters Patent.

Patented May'30, 1922. 1920. Serial No. 380,494.

during the recovering process as will be more clearly hereinafter described.

Secured to the frame F at a point above the tank T are a pair of brackets designated at B and B', each of which comprises a base 2l. a shank 22 and a collar 23 carrying a set .screw 24. The collar of one bracket 'B is arranged in registry with the collar of the bracket B, and extending through these collars is the upper section 25 of a tubular casing K` The casing K is adapted to be engaged by the set screws 24 to effect a secure locking of the same within the brackets so that it will be securely held in vertical position. The lower section 25a of the casing K is rigidly connected at its upper end to the upper section 25 through the medium of a. short pipe fitting 25". The pipe fitting 25" is of the form shown in Figures 1 and 2, it being noted that the diameter of the lower section 25a is less than the diameter of the upper section 25, and because of the contour of the pipe fitting 25b the two casing sections are held in vertical alinement.

Locked within the upper casing section 25 and coextensive in length therewith is a tubular bearing sleeve 26 which is secured within the section by means of set screws 27.

Extending through both the upper and lower sections of the casing K and through the bearing sleeve 26 is a shaft S designed for the purpose of supporting and imparting a rotary motion to an impeller designatedv generally at M. The `upper end of the shaft S projects beyond the upper end of the casing section 25 and is there provided with a pulley 28 that is operatively connected to a similar pulley 29 through the medium of an endless belt 30, the latter being trained over pulleys 31 rotatably supported upon the frame F. The pulley 29 is fixed to one end of the shaft of a motor A as shown in Figure l, the latter being supported upon the horizontal portion of the frame F. The pulleys 28 and 29 are of conical formation and are provided with a plurality `of grooves so that the speed of the shaft S can be varied at will.

The lower endof the shaft S carries the impeller M. and in the present instance the impeller M comprises an upper plate 32 threadedly secured to the lower end of the casing section 25av and a lower plate 33 secured thereto but arranged in spaced relation by means of bosses 34 formed at the periphery of the upper plate 32 and through which bolts 35 extend and threadedly engage the lower plate 33.' As illustrated to advantage in Figures 3 and 5, this manner of attaching the two plates' together provides openings at the periphery of the same through projected, as will be hereinafter described. lVorkng between the plates 32 and 33 1s a disk 36 threadedl secured to the lower end of the shaft S. Secured to or formed lntegral with the opposite sides of the dlsc 36 are two sets-ofblades designated at 37 and 37. The blades of the upper set 37 extend tangentially fromthe hub of the disc 36 to the periphery thereof in vsuch manner that 'adjacent blades are disposed at right angles to each other as clearly shown in Figure 5. The blades of the lower set 37 are arranged upon the lower side of the dlsc 36 at points corresponding to the blades of theupper set 37, but are not coextensive in length therewith as they only extend from the periphery .of the disc inwardly for a relatively short distance. The lower edges of the blades 37a are shaped so as to conform to the general curvature of the upper wall of the late 33, as is clearly shown in Figure 3. he plate 33 is formed axially thereof with an opening, the walls of which are threadedlyengaged by the upper end of a discharge pipe 38.

As clearly shown in Figure 3,v the casing section 25 is disposed in spaced relationto the shaft S so as to provide therebetween an air chamber which communicates at its lower end with the impeller M and at its upper end with the pipe fitting 25h. Air is admitted to this air chamber through a pipe P which as shown in Figures 1 and 2, communicates with and extends laterally from the pipe section 257. This pipe P is controlled by a valve V so that the amount of air entering the air chamber through such pipe can be increased or decreased according to the adjustment of the valve.

In the applied position of the impeller M- as shown in Figure 1, it occupies a position below the deflect-ing plate 20. With the impeller arranged in this position power is now applied to the shaft S through the motor A in the manner previously described, and with rotation of the shaft S a rotary movement is imparted to the disc 36 and the blades 37 and 37 a. The tank l0 is filled with pulp and under the action of the rapidly rotating disc and blades, a suction is created upwardly into the pipe 38 thereby drawing the ore pulp up through thepipe and into contact with the blades 37 Simultaneously with this operation, the upper blades 37 creates a suction downwardly within the air chamber between the shaft S and the lower section casing 25". With the valve V in open position, air enters the air chamber through the pipe P and is thus sucked which the ore pulp is adapted to be Vment of the blades 37 and 37, an intermingling of the ore pulp and airis effected under the action of the blades, and because of the particular arrangement of the latter, the air and ore pulp are thrown, under the action of centrifugal force, outwardly from the periphe of the plates 32 and 33 and into the tank This action of the impeller M creates air bubbles in-a manner which will be well understood, and these an' bubbles in their upward passage within the tank T attach themselves to the valuable mineral particles of the ore pulp, carrying them to the surface where they are discharged over the lip 17. The plate 20 functions to prevent the passage of the undesirableparticles of the ore downwardly to a point adjacent the impeller, as will be understood.

Should the character of the ore pulp being treated be such as to warrant an increase or decrease in the amount of air supplied to the impeller M, it will be clear from the foregoing description that the volume of air supplied to the impeller canbe readily regulated at the will of the p7perator through the l medium of the valve Although I have herein shown and described only one form of otation apparatus embodying my invention, it is to be understood that various changes and modifica-l tions may be made herein -without departlng -from the spirit of the invention and the spint and scope of the appended claims.

What I claim is;

1. A flotation apparatus comprising, a tank, an impeller within the tank comprising spaced plates, a disc between the plates, blades secured to the opposite sides of the disc, means for rotating said disc, and means for supplying ore pulp to one side of the dlsc and alr to the opposite side, for the purpose described.

2. A flotation apparatus, comprising, a

tank, an impeller within the tank compris-v ing spaced plates, a disc between theY plates, blades secured to the opposite sides of the dlsc, means for rotating said disc, means for supplylng ore pulp to one sider of the disc and air to the opposite side, and means for controlling the supply of air to the disc.

3. .A flotation apparatusA comprising, a tank, a pulp conducting pipe within the tank, an air conducting pipe wit-hin the tank, and an impeller arranged between said pipes, said impeller comprising a pair of spaced plate, a rotatable discA between said plates, blades secured to the opposite sides ofsaid disc, an means for rotating said dise.

4. A fiotation apparatus comprising, a tank, a pulp conducting pipe within the tank, an air conducting pipe extending into the tank, plates secured to the confronting ends of said pipes and spaced apart in parallelism,

a shaft within the air conducting pipe, a dis'c fixed to said shaft and interposed between said plates, blades secured to the opposite sides of said dise, means for rotating said shaft, and means for controlling the supply of air to said air conducting pipe.

5. A flotation apparatus, comprising, a tank, a pulp conducting pipe Within the tank, an air conducting pipe extending into the tank2 plates secured to the confronting ends of sald pipes and spaced apart in parallelism, a shaft Within the air conducting pipe, a disc fixed to said shaft and interposed between said plates, blades secured to the opposite sides of said disc, means for rotating said shaft, means for controlling the supply of air to said air conducting pipe comprising, a pipe arranged exteriorly of the tank and communicating with the air conducting pipe, and a valve Within said pipe.

6. An' impeller of the character described comprising, spaced plates, a disc rotatable between the plates, and sets of blades secured to the opposite side of said disc with the blades of each set arranged at right angles to each other.

7. An impeller of the character described comprising, a pair of pipes arranged with their ends in confronting relation, plates secured to the confronting ends of the pipes and spaced apart, a shaft extending through one of the pipes, a disc fixed to said shaft and interposed between said plates, and sets of blades secured to the opposite sides of said disc, the blades of both sets being disposed at right angles to each other and the blades of one set being relatively short as compared to the blades of the other set.

8. A flotation apparatus comprising a tank, an air conducting pipe extending into the tank to a point adjacent the bottom thereof, a pulp conducting pipe arranged in confronting rela-tion to the lower end of the air conducting pipe and in communication With the tank, a disk rotatably mounted between said pipes, plates secured to the opposite sides of said disk, means for rotating said disks wherebysuction Will be created Within said pipes, and a baffle plate Within the tank for the purpose described.

ARTHUR W. FAHRENWALD. l 

